Background. Over 6 million people live in areas of West Bengal, India, where groundwater sources are contaminated with naturally occurring arsenic. The key objective of this nested case-control study was to characterize the dose-response relation between low arsenic concentrations in drinking water and arsenic-induced skin keratoses and hyperpigmentation. Methods. We selected cases (persons with arsenic-induced skin lesions) and age- and sex-matched controls from participants in a 1995–1996 cross-sectional survey in West Bengal. We used a detailed assessment of arsenic exposure that covered at least 20 years. Participants were reexamined between 1998 and 2000. Consensus agreement by four physicians reviewing the skin lesion photographs confirmed the diagnosis in 87% of cases clinically diagnosed in the field. Results. The average peak arsenic concentration in drinking water was 325 μg/liter for cases and 180 μg/liter for controls. The average latency for skin lesions was 23 years from first exposure. We found strong dose-response gradients with both peak and average arsenic water concentrations. Conclusions. The lowest peak arsenic ingested by a confirmed case was 115 μg/liter. Confirmation of case diagnosis and intensive longitudinal exposure assessment provide the basis for a detailed dose-response evaluation of arsenic-caused skin lesions.
There has been widespread speculation about whether nutritional deficiencies increase the susceptibility to arsenic health effects. This is the first study to investigate whether dietary micronutrient and macronutrient intake modulates the well-established human risk of arsenic-induced skin lesions, including alterations in skin pigmentation and keratoses. The study was conducted in West Bengal, India, which along with Bangladesh constitutes the largest population in the world exposed to arsenic from drinking water. In this case–control study design, cases were patients with arsenic-induced skin lesions and had < 500 μg/L arsenic in their drinking water. For each case, an age- and sex-matched control was selected from participants of a 1995–1996 cross-sectional survey, whose drinking water at that time also contained < 500 μg/L arsenic. Nutritional assessment was based on a 24-hr recall for major dietary constituents and a 1-week recall for less common constituents. Modest increases in risk were related to being in the lowest quintiles of intake of animal protein [odds ratio (OR) = 1.94; 95% confidence interval (CI), 1.05–3.59], calcium (OR = 1.89; 95% CI, 1.04–3.43), fiber (OR = 2.20; 95% CI, 1.15–4.21), and folate (OR = 1.67; 95% CI, 0.87–3.2). Conditional logistic regression suggested that the strongest associations were with low calcium, low animal protein, low folate, and low fiber intake. Nutrient intake was not related to arsenic exposure. We conclude that low intake of calcium, animal protein, folate, and fiber may increase susceptibility to arsenic-caused skin lesions. However, in light of the small magnitude of increased risks related to these dietary deficiencies, prevention should focus on reducing exposure to arsenic.
Background: The main purpose of this paper is to understand the multidimensional phenomenon of the nutrition transition in Malaysia, from 1980 to 2014, to inform future policies for a healthier nation. Methods: Food and health data were obtained through Food Balance Sheets, Malaysian Adult Nutrition Survey (MANS) and National Health and Morbidity Surveys (NHMS) for year-to-year review. Interaction between changes in food supplies and dietary trends and the progression of diet-related diseases and risk factors in tandem with demographic and socioeconomic transitions were observed using quasi-historical approach. Results: The period-under-review has seen Malaysia becoming more affluent, urbanised and modernised. Energy supply for Malaysian population remained consistently in excess of average calorie needs by a minimum of 30%. There were significant signs of shifting food trends, particularly in the supply of wheat (+ 56.5%), rice (− 23.7%), sugar and sweeteners (+ 23.9%), meat (+ 49.3%), fish and seafood (+ 38.7%), and eggs (+ 55.7%). The plant/animal protein ratio has decreased over time. Prevalence of NCD and associated risk factors has increased rapidly, some as high as 170%, despite various policy efforts to reduce them. Conclusion: The study highlights the importance of policymakers taking a relook into its policies and strategies, and formulate sustainable, comprehensive and multifaceted actions together with all relevant stakeholders to ensure a conducive, healthy and nutritious food systems and environment for its population.
1 September 2011 in Environmental Health Perspectives
Suboptimal vitamin D status among the South Asian UK population is widely reported; however, its impact on bone health is unclear. The aim of the present study was to conduct a comparative investigation of vitamin D status in postmenopausal South Asian (SA) and Caucasian (C) women and its relationship to parathyroid hormone (PTH) concentration, biochemical markers of bone turnover and bone quality. A cross-sectional study of community-dwelling women aged 50-66 years was carried out. A total of sixty-six SA women of Pakistani origin and forty-two C women living in the same community were recruited. Fasting blood was taken for the measurement of vitamin D, PTH and biochemical markers of bone turnover, including type-1 collagen beta C-telopeptide (betaCTX), procollagen type-1 amino-terminal propeptide (P1NP), and bone-specific alkaline phosphatase (BAP) activity. Bone quality was assessed using broadband ultrasound attenuation (BUA). Total serum 25-hydroxyvitamin D (25(OH)D) was significantly lower in the SA women than the C women (medians: SA 10.5 v. C 47.1 nmol/l; P < 0.001) This was associated with a significantly elevated serum PTH concentration in the SA group (medians: SA 7.3 v. C 4.5 pmol/l; P < 0.01). BAP activity was also significantly higher in the SA group, indicating elevated osteoblast activity and bone turnover (medians: SA 23.0 v. C 20.0 U/l; P < 0.05). No significant differences were observed between the two groups for P1NP, betaCTX or BUA. Although the SA women had significantly higher serum PTH and lower 25(OH)D concentrations than C women, this was not associated with significantly higher markers of bone resorption, or reduced bone quality in the SA women.